Download or read book Heisenberg Antiferromagnetic Model on 2D Quasiperiodic Tilings written by Attila Szàllàs and published by . This book was released on 2008 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Penrose tiling is a perfectly ordered two dimensional structure with fivefold symmetry and scale invariance. We considered a Heisenberg antiferromagnet on the Penrose rhombus tiling, and showed it has an inhomogeneous Neel-ordered ground state. Spin wave energies and wavefunctions were studied in the linear spin wave approximation. Spatial properties of eigenmodes were characterized in several different ways. At low energies, eigenstates were found to be relatively extended, and appeared to show multifractal scaling. At higher energies, states were found to be more localized, and, depending on the energy, confined to sites of a specified coordination number. The ground state energy of this antiferromagnet, and local staggered magnetizations were calculated. Perpendicular space projections were shown, showing the underlying simplicity of this "complex" ground state. A simple analytical model, the two-tier Heisenberg star, was presented to explain the staggered magnetization distribution in this antiferromagnetic system. The effects of a novel type of disorder in a two dimensional quantum antiferromagnet is considered. The original bipartite structure is geometrically disordered in such a way that no frustration is introduced, and the system retains a Neel ordered ground state. We show, using a linear spin wave expansion and QMC, that the staggered moment decreases exponentially as a function of increasing disorder. The spatial distribution of staggered magnetizations becomes more homogeneous compared to the deterministic tiling, the effective spin wave velocity increases with disorder, and singularities in the magnon spectrum and wavefunctions are partly smoothed.
Download or read book Two layer Heisenberg Model of Quasi 2D Triangular Lattice Antiferromagnet and Study of the Magnetoelastic Coupling in Ba3CoSb2O9 Using Sound Velocity Measurements written by Ming Li and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The magnetic field evolution of ground spin states of the stacked planar triangular antiferromagnet with antiferromagnetic interlayer interaction Jc is explored using a minimal 3D classical Heisenberg model (published in Ref. [1]). A bi-quadratic coupling is also used to mimic the effect of spin fluctuations [2] which are known to stabilize the magnetization plateau. A single ion anisotropy is included and states with a magnetic field applied in the ab-plane and along the c-axis are determined. For H || ab-plane, an additional state, in contrast to the 2D model [2], is obtained with weak interlayer interaction. Meanwhile the magnetization plateau decreases with the increment of Jc and vanishes at medium values of Jc. Moreover, two new states with a small z components of spins emerge with large Jc. For H || c-axis, an extra state, compared with the 2D model, is obtained with a weak interlayer interaction. When Jc is large enough, only the state corresponding to the Umbrella phase in the 2D model exists. High-resolution ultrasonic measurements are used to study magnetoelastic coupling as a function of the inplane magnetic field orientation in the spin-1/2 triangular lattice antiferromagnet Ba3CoSb2O9 (published in Ref. [3]). Via these measurements, the relevance of this coupling in stabilizing the 1/3 magnetization plateau (up-up-down state) is explored. The analysis indicates that, while the magnetoelastic coupling in Ba3CoSb2O9 is large, in comparison to other triangular lattice antiferromagnets, the strength of this coupling is still too small to fully account for the magnetization plateau width in Ba3CoSb2O9. Spin fluctuations are therefore the dominant mechanism inducing and stabilizing the magnetization plateau. Our results also show that the amplitude of the spin fluctuations suddenly drops as the V phase is induced at higher field. Furthermore, as the temperature approaches the uud phase boundary from the paramagnetic state, the short range spin correlation, responsible for the softening of the acoustic modes, are also observed. Comparing the experimental results in ordered states at different temperatures, our results indicate that the effect of the thermal fluctuations on the magnetoelastic coupling are negligible at low temperatures in comparison to that of the quantum fluctuations.
Download or read book An Introduction to Quantum Spin Systems written by John B. Parkinson and published by Springer Science & Business Media. This book was released on 2010-09-20 with total page 159 pages. Available in PDF, EPUB and Kindle. Book excerpt: The topic of lattice quantum spin systems is a fascinating and by now well established branch of theoretical physics. Based on a set of lectures, this book has a level of detail missing from others, and guides the reader through the fundamentals of the field.
Download or read book Zeitschrift F r Kristallographie written by and published by . This book was released on 2009 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Digests of Intermag written by and published by . This book was released on 1998 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Introduction to Condensed Matter Physics written by Duan Feng and published by World Scientific. This book was released on 2005 with total page 612 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is volume 1 of two-volume book that presents an excellent, comprehensive exposition of the multi-faceted subjects of modern condensed matter physics, unified within an original and coherent conceptual framework. Traditional subjects such as band theory and lattice dynamics are tightly organized in this framework, while many new developments emerge spontaneously from it. In this volume,? Basic concepts are emphasized; usually they are intuitively introduced, then more precisely formulated, and compared with correlated concepts.? A plethora of new topics, such as quasicrystals, photonic crystals, GMR, TMR, CMR, high Tc superconductors, Bose-Einstein condensation, etc., are presented with sharp physical insights.? Bond and band approaches are discussed in parallel, breaking the barrier between physics and chemistry.? A highly accessible chapter is included on correlated electronic states ? rarely found in an introductory text.? Introductory chapters on tunneling, mesoscopic phenomena, and quantum-confined nanostructures constitute a sound foundation for nanoscience and nanotechnology.? The text is profusely illustrated with about 500 figures.
Download or read book Scale Invariance written by Annick LESNE and published by Springer Science & Business Media. This book was released on 2011-11-04 with total page 406 pages. Available in PDF, EPUB and Kindle. Book excerpt: During a century, from the Van der Waals mean field description (1874) of gases to the introduction of renormalization group (RG techniques 1970), thermodynamics and statistical physics were just unable to account for the incredible universality which was observed in numerous critical phenomena. The great success of RG techniques is not only to solve perfectly this challenge of critical behaviour in thermal transitions but to introduce extremely useful tools in a wide field of daily situations where a system exhibits scale invariance. The introduction of scaling, scale invariance and universality concepts has been a significant turn in modern physics and more generally in natural sciences. Since then, a new "physics of scaling laws and critical exponents", rooted in scaling approaches, allows quantitative descriptions of numerous phenomena, ranging from phase transitions to earthquakes, polymer conformations, heartbeat rhythm, diffusion, interface growth and roughening, DNA sequence, dynamical systems, chaos and turbulence. The chapters are jointly written by an experimentalist and a theorist. This book aims at a pedagogical overview, offering to the students and researchers a thorough conceptual background and a simple account of a wide range of applications. It presents a complete tour of both the formal advances and experimental results associated with the notion of scaling, in physics, chemistry and biology.
Download or read book Competing Interactions and Pattern Formation in Nanoworld written by Elena Vedmedenko and published by John Wiley & Sons. This book was released on 2007-02-27 with total page 215 pages. Available in PDF, EPUB and Kindle. Book excerpt: Systems displaying competing interactions of some kind are widespread - much more, in fact, as commonly anticipated (magnetic and Ising-type interactions or the dynamics of DNA molecules being only two popular examples). Written for researchers in the field with different professional backgrounds, this volume classifies phenomena not by system but rather by the type of competing interactions involved. This allows for a straightforward presentation of the underlying principles and the universal laws governing the behaviour of different systems. Starting with a historical overview, the author proceeds by describing self-competitions of various types of interactions (such as diploar or multipolar interactions), competitions between a short-range and a long-range interaction (as in Ising systems or DNA models) or between a long-range interaction and an anisotropy (as in ultrathin magnetic films or magnetic nanoparticles) and finally competitions between interactions of the same range (as in spin glasses). Each chapter contains a few problems with solutions which provide suitable material for lecturers of mathematics and physics as well as biology courses. A vast body of references to the original literature make the volume self-contained and ideally suited to master this interdisciplinary field.
Download or read book Physics Briefs written by and published by . This book was released on 1994 with total page 1224 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Computer Simulation Studies in Condensed Matter Physics X written by David P. Landau and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt: Computer Simulation Studies in Condensed-Matter Physics X is devoted to Prof. Masuo Suzuki's ideas, which have made novel, new simulations possible. These proceedings, of the 1997 workshop, comprise three parts that deal with new algorithms, methods of analysis, and conceptual developments. The first part contains invited papers that deal with simulational studies of classical systems. The second of the proceedings is devoted to invited papers on quantum systems, including new results for strongly correlated electron and quantum spin models. The final part contains a large number of contributed presentations.
Download or read book Introduction to Frustrated Magnetism written by Claudine Lacroix and published by Springer Science & Business Media. This book was released on 2011-01-12 with total page 682 pages. Available in PDF, EPUB and Kindle. Book excerpt: The field of highly frustrated magnetism has developed considerably and expanded over the last 15 years. Issuing from canonical geometric frustration of interactions, it now extends over other aspects with many degrees of freedom such as magneto-elastic couplings, orbital degrees of freedom, dilution effects, and electron doping. Its is thus shown here that the concept of frustration impacts on many other fields in physics than magnetism. This book represents a state-of-the-art review aimed at a broad audience with tutorial chapters and more topical ones, encompassing solid-state chemistry, experimental and theoretical physics.
Download or read book Journal of Physics A written by and published by . This book was released on 2000 with total page 724 pages. Available in PDF, EPUB and Kindle. Book excerpt: Focuses on fundamental mathematical and computational methods underpinning physics. Relevant to statistical physics, chaotic and complex systems, classical and quantum mechanics, classical and quantum integrable systems and classical and quantum field theory.
Download or read book Lecture Notes on Condensed Matter Physics a Work in Progress written by Daniel Arovas and published by . This book was released on 2014-12-17 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lecture Notes on Condensed Matter Physics (A Work in Progress)By Daniel Arovas
Download or read book Microscopic Aspects of Nonlinearity in Condensed Matter written by Alan R. Bishop and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 357 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of a NATO ARW held in Florence, Italy, June 7--13, 1990
Download or read book From Newton to Mandelbrot written by Dietrich Stauffer and published by Springer. This book was released on 2013-11-11 with total page 233 pages. Available in PDF, EPUB and Kindle. Book excerpt: From Newton to Mandelbrot takes the student on a tour of the most important landmarks of theoretical physics: classical, quantum, and statistical mechanics, relativity, electrodynamics, and, the most modern and exciting of all, the physics of fractals. The treatment is confined to the essentials of each area, and short computer programs, numerous problems, and beautiful color illustrations round off this unusual textbook. Ideally suited for a one-year course in theoretical physics it will also prove useful in preparing and revising for exams. This edition is corrected and includes a new appendix on elementary particle physics, answers to all short questions, and a diskette where a selection of executable programs exploring the fractal concept can be found.
Download or read book Spin Ice written by Masafumi Udagawa and published by Springer Nature. This book was released on 2021-10-19 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book deals with a new class of magnetic materials, spin ice. Spin ice has become the canonical example of modern frustrated magnetism where competing interactions between spins set the rules for an emergent magnetostatic gauge field theory. Excitations take the form of magnetic monopoles or can condense via a Higgs mechanism. Beyond classical spin ice, the book describes the new physics emerging when quantum coherence (spin liquids, photon-like excitations) and itinerant electrons (anomalous Hall effect) are included in artificial systems. This first book dedicated to spin ice is a review of the current understanding of the field, both on the theoretical and experimental levels, written by leading experts. The book is written in a linear way with very few prerequisites. It also contains textbook-like descriptions of theoretical methods to help advanced students and researchers to enter the field.
Download or read book Chaotic Fractional and Complex Dynamics New Insights and Perspectives written by Mark Edelman and published by Springer. This book was released on 2017-11-17 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book presents nonlinear, chaotic and fractional dynamics, complex systems and networks, together with cutting-edge research on related topics. The fifteen chapters – written by leading scientists working in the areas of nonlinear, chaotic, and fractional dynamics, as well as complex systems and networks – offer an extensive overview of cutting-edge research on a range of topics, including fundamental and applied research. These include but are not limited to, aspects of synchronization in complex dynamical systems, universality features in systems with specific fractional dynamics, and chaotic scattering. As such, the book provides an excellent and timely snapshot of the current state of research, blending the insights and experiences of many prominent researchers.
